One vertex per element, one color per generator, with an edge from x to x·s.
(2,5)(6,8)(9,10,14,17)(11,12,19,15)(13,21,22,16)(18,23,24,20)(28,36)(32,37)(34,40)(38,39)(2,5)(3,7)(9,11)(10,15)(12,17)(13,18)(14,19)(16,23)(20,21)(22,24)(26,30)(31,33)(32,37)(38,39) involution — undirected(1,2,4,5)(3,6,7,8)(9,11,14,19)(10,15,17,12)(13,18,22,24)(16,23,21,20)(25,26)(27,33)(28,32)(29,30)(31,35)(34,39)(36,37)(38,40)(1,3,4,7)(2,6,5,8)(9,12)(10,11)(13,20)(14,15)(16,18)(17,19)(21,24)(22,23)(9,11)(10,12)(13,18)(14,19)(15,17)(16,20)(21,23)(22,24)(25,27,29,35)(26,31,30,33)(28,34,36,40)(32,38,37,39)(9,13,14,22)(10,16,17,21)(11,18,19,24)(12,20,15,23)(25,28)(26,32)(27,34)(29,36)(30,37)(31,38)(33,39)(35,40)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.